Dual carburetor adapter



Feb. 27, 1940. 5. c. BETRY DUAL CARBURETOR ADAPTER Filed May 16, 1959 2 Sheets-Sha e! 1 :Ilglm 7 I Feb.27, 1940. f j -RY 2,192,067.

DUAL CARBURETOR ADAPTER Filed May 16, 1939 2 Sheets-Sheet 2 ljtlq7 QMWM 33 0.61565 v Patented Feb. 27, 1940 UNITED- STATES PATENT OFFICE" 8 Claims.

My invention relates to a novel fuel temperature" regulator and distributor adapted for use on gas engines and has particular reference to a device that may be installed on existing types of engines in which a dual carburetor system is employed. The temperature regulator and distributor has the double function of controlling the temperature of the supply of fuel mixture from each carburetor and, at the same time, provides a means for by-passing a portion of vaporized gasoline from the carburetors directly to the end cylinders.

' In the modern types of multiple cylinder high speed gas engines, certain notable difficulties in operation have been encountered. In the first instance, it has been found necessary to supply additional fuel to the engine during overload operating periods by means of an auxiliary carburetor associated in a parallel fluid circuit with the customary gas engine carburetor. Again, it has been found that in gas engines using ordinary intake manifolds the end cylinders particularly are starved in that they do not receive the same proportion of vaporized fuel as do the other cylinders. There is the further objection that the temperature of the vaporized fuel within the manifold varies in a wide range in accordance with the ambient air temperatures and is, at times, too hot and, at other times, too cool for efficient operation of the engine. According to my invention, an apparatus is provided that functions both to more properly distribute the fuel supplied by a dual carburetor system to the various cylinders and to control the temperature of this fuel at all times.

The main object of my invention is to provide a means which is readily adapted for installation on existing engines provided with dual carburetor systems in a manner to permit an auxiliary or shunt supply of fuel mixture from the carburetors to each end cylinder. I

Another object is to provide auxiliary means for heating the fuel mixture during the starting cycle of the operationof the engine.

Another object is to provide means for heating or cooling the fuel mixture according to the-temperature of the crank case oil and for heating cool crank case oil.

For a full disclosure of the invention, reference is made to the accompanying drawings, wherein- Fig. 1 shows the device, with parts removed, as associated with the dual carburetor system and intake manifold;

1 Fig. 2 is a bottom plan view of the device;

Fig. 3is an end view of the device;

Fig. 4 is a top removed;

Fig. 5 is a side view of the device;

Fig. 6 is a view'in section on line 6-6 of Fig.

plan view of the device with parts 2 and "6-" Fig. 7 is a view in detail of an electric fuelizer associated with one carburetor.

Referring to the drawings in detail, the invention is shown as applied to a duplex manifold l of a V4; motor which is provided with dual car- 10 buretors 2, and 2'. g The carburetors 2-2 are conventional in type, being provided with the usual butterfly valves 3 and 3' to control the supply of fuel mixture to the intake manifold. A fuel line supplies both carburetors. The essential feature of my invention comprises an adapter unit 5, preferably a casting, which is adapted to be inserted between theintake neck ii of the manifold and the bases of the carburetors 2 and 2. The manifold shown is adapted 20 to supply opposed banks of cylinders and the intake neck 6 is provided with two vertical conduits 'i, one for each bank of cylinders leading to the horizontal manifold passage 1'. An electric heater'ii shown in detail in Fig. 7 is inserted be- 25 tweenthe adapter unit 5 and the carburetor '2 which is mounted directly over the intake neck 6.

Referring to Fig.2, the adapter unit casting 5 is provided with a pair of gas intake conduits 9 and 9' which are surrounded by'a thin wall I0. 30 The casting 5 is further provided with intake openings i l and i l which are connected by snailshaped channels i2 and !2' to conduits 99' at right angles thereto. An oil reservoir l 3 is formed around the wall iii within the casting 5. The res- 3-5 ervoir is arcuate, conforming with wall It) and is divided by a partition I4. The casting'5 is tapped at it and Hi to receive fittings I1 and I8, respectively. The average depth of the reservoir is approximately an eighth of an inch. The depth of the reservoir is greatest adjacent the taps l5 and it where the reservoir is deepened to provide wells. The well at outlet tap I6 is preferably about a quarter of an inch deep, while the well at inlet tap i5 is relatively much deeper.

Oil is pumped from the crank case through a feed pipe I9 into one end of the reservoir I 3 and around the wall iii of the conduits 9-9. The oil leaves the reservoir by tap IBand return pipe 29 which leads to the crank case. A gasket 21 50 seals the lower face of the casting 5 and closes the reservoir H! from below.

Referring to Fig. 4, the adapter unit casting 5' is tapped at 22 and 22' ina manner to commu nicate with gas conduits" 9--9 and channels 55 each of the four end cylinders.

I 2-l2' at right angles therewith. The taps receive nipples 23 and 23 which are connected to T-shaped fittings 24 and 24. The fittings are connected to four conduits 25 which are tapped, respectively, into the manifold at points opposite The adapter unit casting 5 is provided with three bolt openings 26 which receive three stud bolts 21 which extend from the manifold intake neck 6 and nuts 28 serve to hold the carburetor 2 and the casting 5 in po sition on the manifold. The casting 5 is further provided with stud bolts 29 which extend through the base of carburetor 2 and nuts 30 which serve to secure the carburetor 2' to the adapter unit.

Referring to Fig. 6, the View in cross section of the adapted unit 5 shows the walls of the intake conduits 99' tapered to provide a constriction at the lower ends thereof. The taper of the intake conduits causes an increase in the static pressure of the fuel mixture flowing therethrough. The increased static pressure assists in diverting a portion of the fuel mixture from the conduits 99'. into the passages 22 and 22'. The intake conduits 99' are further provided with cylindrical screens 3| which serve as baflies or mixers. It will be noted in this figure as well as in Fig. 2 and Fig. 4, that the snail-shaped channels I2-l2 vary in diameter throughout their length becoming increasingly smaller at the outlet end. The constriction of the channels adjacent their outlet causes a high turbulence of the fuel mixture which is extremely desirable for reasons hereinafter stated.

The electric heater and mixer shown in detail in Fig. '7 comprises a non-conducting member 32 provided with openings 33 which are co-extensive with the fuel supply throat openings of the carburetor and the intake conduits 9-9; in. adapter unit 5. The openings 33 contain cupshaped member 34 having perforated bottoms 35. Heating coils 35 are secured to the outside of the bottoms of cups 754 and are insulated therefrom by plates 31. A source of current is supplied to the coils 36 through wires 38 and anchor bolts 39. The cups are mounted in the intake passage on the side thereof adjacent the lower or depending edge of the butterfly valve 3. p

In operation, a mixture of fuel and air is drawn downwardly from the carburetor 2 around the butterfly valves 3 in the intake passages. The fuel mixture flows in part through the perforated bottoms 35 of the electric heater and mixer B and over coils 36 where the fuel mixture is further vaporized and agitated. The fuel mixture then flows through the intake conduits 9-9' in the adapted unit 5. Portions of the fuel mixture are by-passed from the conduits 9-9 through a respective conduit 25 into each end cylinder. The static pressure increase resulting from the constriction of conduits l2i2, as well as the intake suction of the end cylinders through pipes 25, assists in the mixing of the fuel. At the same time, oil is pumped in from pipe is through reservoir l3 to substantially surround conduits 9-9, thence out through return pipe 25 and back to the crank case in a manner to heat or cool the incoming stream of fuel mixture, depending upon the temperature of such mixture with respect to that of the crank case oil.

When the engine is operated with an overload such as a high speed operating period, additional fuel mixture is supplied by carbuetor 2 toopenings l 1-! i in the adapter unit 5. The fuel mixture flows through the snail-shaped channels 12-42 to the passages 2242* and conduits 99. The shape of the channels l2.-l2' cause high turbulence of the fuel mixture adjacent the coils 36 as a result of the constriction of the channels as. above described, whereby a portion of the gas from channels l2--|2' is drawn up against the hot coils 36. The gas leaves the reduced ends of these channels at an increased pressure and expansion of this gas into the en:

larged chamber adjacent coils 36 occurs at a reduced pressure according to the law of a Venturi tube. The relative differences-of pressures of gas at this point from the two carburetors causes high turbulence and formation of eddy currents and efiicient mixing of the two streams of gas at.

different temperatures. It will be noted that, in Fig. 6, the coils 36 are positioned but slightly above the ends of the channels l2--l2 and are positioned on that side of conduits 99 adjacent said channel ends. Also as viewed in Fig. 1, the coils 35 are positioned just below the lower ends of the butterfly valves and are secured to the right hand side of the passages 99 whereby, as shown by the arrows, the major portion of the gas which is shown as flowing around'the right hand side of these valves is divertedthrough the coils 36 and, immediately thereafter,

meets the gas streams from channels l2-l2. During engine startingand at slow speed operation thereof, the cylinders are supplied by gas from carburetor 2, which gas stream is highly heated by coils 36. It will be noted from Fig. .4

that the gas streamsfromchannels l2!2 are.

directed at a sharp angle to the passages 22'22 The oil groove 83 is located at the lower end of the unit 5 to ensure a more practical distributtion of heat from the oil since the heat therefrom has a greater tendency to flow upwardly.

I claim: 1. In a gas engine, an adapter casing adapted to be secured in operative position between a pair of carburetors and a manifold, said casing being provided at one end with a main gas conduit extending therethrough from an upper face to a lower face thereof, said casing being provided with an auxiliary gas conduit formed in the body of the casing, one end of the auxiliary conduit terminating in said upper face adjacent the other end of the casing and extending through the body of the casing and being'connected at-its other end tothe main conduit, and means for securing a carburetor to each end of the casing in position to feed gas to said conduits.

2. In a device as set forth in claim 1 wherein the auxiliary conduit is tapered to providea reduced cross section adjacent the point of connection thereof to the other conduit.

3. In a device as set forth in claim 1, a heating;

means positioned within the mainconduit adjacent the connection of the gas outlet whereby a heated portion of gas may be drawn from the main conduct into the outlet and another portion drawn from the auxiliary conduit.

4. In a gas engine having cylinders, a pair of carburetors and an intake manifold, an adapter casing secured to and between the carburetors. and the manifold, a main gas conduit formed in said casing and extending between the upper and the lower face thereof at one end of the casing, a gas outlet formed in the casing and extending from said main conduit to one side of the casing, a pair of feeder conduits extending from said outlet and being connected respectively to opposite ends of the manifold adjacent the end cylinders, an auxiliary conduit having its inlet end positioned-at the. other end of the casing and extending therethrough and being connected to said first-named conduit adjacent the point of connection of the gas outlet whereby to'feed gas" therethrough tos'aid first-named conduit and said outlet, said carburetors being mounted on saidcasing to feed gas to said donduits'respectively.

v 5. In a gas engine having cylinders, a pair of carburetors and an intake manifold, an adapter unit secured to and betweenthe carburetors and the manifold, a maingas conduit formed in one end of said unit, a gas outlet formed in the unit and extending from said main conduit intermediate its ends to a side of the unit, an auxiliary v conduit having its inlet end positioned at the other end of the unit and extending therethrough and being connected to said main conduit adjacent the point of connection of the gas outlet, a

pair offeeder conduits extending from said gas outlet and being connected respectively to opposite ends of the manifold: adjacent the end cylinders, a pair of carburetors secured to said adapter unit and positioned over the main gas conduit and the-inlet end of said auxiliary conduit, a gas heater interposed between said main gas conduit and the adjacent carburetor, whereby a supply of gaseous fuel is delivered from a point above said heater and an auxiliary supply of gaseous fuel is delivered from the other carburetor to a point below and adj acent said heater, a portion of said gaseous fuel being withdrawn and delivered through said feeder conduits to the end cylinders.

tion of said conduit and a butterfly valveassociated with the carburetor positioned above said maingas conduit adapted to deflect a major portion of the gaseous fuel to said heater.

8. In a-gas engine, an adapter casing adapted to be secured between a pair of carburetors and a manifold, said casing being provided at one end with a main gas conduit extending vertically therethrough, .an end cylinder gas outlet extend- I ing from the main conduit to one side of the casing, conduits for connecting said outlet to respective ends of the manifold adjacent end cylinders, an auxiliary gas conduit extending from the other end ofsaid casing and opening into said outlet and main conduit adjacent the point of connection therebetween, and means for securing a carburetor to each end of the casing in position to feed gas to the main and auxiliary conduits.

OWEN CHARLES BE1RY.' 

